CVS
First time you use the MPlayer CVS, issue the commands
cvs -d:pserver:anonymous@cvs.mplayer.sourceforge.net:/cvsroot/mplayer login
cvs -z3 -d:pserver:anonymous@cvs.mplayer.sourceforge.net:/cvsroot/mplayer co main
A directory named main will be created, with the sources.
Later you'll only have to do
cd main
cvs update
if you want the most up-to-date version.
Precompiled binaries
(not yet)
Precompiled packages
(not yet)